The major goal, which we expect to reach within three years, is to generate an accessible library of closely related, partially characterized, transplantable B-cell lymphomas in a single inbred strain of mice. En route to this objective a number of ancillary benefits will accrue. Specifically, we aim to accomplish the following: 1. By procedures involving intense antigenic stimulation to induce a large number (more than 50) of primary lymphoid tumors in B10.H-2aH-4bp/Wts(2a4b) mice. Most of these will be B-cell lymphomas (vide infra) with a minority of T-cell and macrophage tumors. Most of these tumors will be transplantable in 2a4b mice and most will convert readily to an ascites form. 2. From the above primaries, to establish a series of transplantable tumors such that 50 independently derived B-cell lymphomas are included. Cell suspensions from primary and early transplant generations of all tumors will be stored under liquid nitrogen. 3. To characterize, with respect to a battery of cell surface differentiation markers, the cells of each tumor which becomes established in transplantation. 4. To prepare specific xenogeneic anti-idiotype sera against the surface immunoglobulin of each independently derived B-cell lymphoma. 5. To determine the extent of cross-reactivity between the idiotypes of the surface immunoglobulins of the 50 independently derived B-cell lymphomas. 6. To catalog, with respect to surface differentiation markers, those B-cell, T-cell and macrophage tumors which become established in transplantation and to make such tumors, together with histocompatible mice for transplantation, available for study by other interested investigators.